Sand blowing apparatus



March 30, 1965 R. c. HATHORN 3,175,735

SAND BLOWING APPARATUS Filed May 29, 1963 TOR.

Affarngms ited tates Patent 3,175,735 SAM) BLOWING APPARATUS Ray C.Hathorn, 1309 Kilby Terrace, Anniston, Ala. Filed May 29, 1963, Ser. No.284,088 Claims. (61. 222-193) This invention relates to sand blowingapparatus and more particularly to such apparatus which shall be adaptedto force sand in a positive manner from a sand supply means to a sandreceiving member, such as a core box, a mold to be sand-lined and thelike.

An object of my invention is to provide sand blowing apparatus in whichthe sand is conveyed into the sand receiving member with a minimum ofcompressed air, thereby eliminating sand blasting.

Another object of my invention is to provide sand blowing apparatus ofthe character designated in which the mass of sand is not introducedinto an open space or voids in the apparatus prior to reaching the sandreceiving member, thereby providing a constant sand to air ratio as thesand is introduced into the sand receiving member.

Another object of my invention is to provide sand blowing apparatus ofthe character designated in which there are no large expansion chambersWhich tend to lower the temperature of the sand prior to beingintroduced into the sand receiving member.

A further object of my invention is to provide sand blowing apparatus ofthe character designated which is simple of construction, economical ofmanufacture and which requires no conveyors or the like for supplyingsand to the apparatus.

Briefly, my improved sand blowing apparatus comprises sand supply meanscommunicating with a blow head by a conduit which extends downwardlyfrom the sand supply means and terminates in an upwardly extendingportion which is connected to the blow head. Air supply meanscommunicates with the conduit subjacent the sand supply means and meansis provided to control the flow of air from the air supply means to theconduit whereby the supply of compressed air may be interrupted. Valvemeans is provided which is operable in response to introduction of airinto the conduit to block the flow of sand from the sand supply meansand to block the fiow of air from the conduit into the sand supply meansto thereby force the sand through the blow head into the sand receivingmember, Also, the valve member is disposed to permit gravity flow ofsand from the sand supply means to the conduit in response tointerruption of the flow of air from the air supply means to the conduitto thereby fill the conduit with sand.

Apparatus embodying features of my invention is illustrated in theaccompanying drawing, forming a part of this application, in which:

FIG. 1 is a side elevational view of the sand blowing apparatus;

FIG. 2 is an enlarged, fragmental view showing the means for introducingair and sand into the conduit which supplies sand to the blow head; and,

FIG. 3 is a sectional view taken generally along the line 3-3 of FIG. 2.

Referring now to the drawing for a better understanding of my invention,I shoW a sand supply hopper which preferably has a downwardly convergingbottom wall 11. The lower end of the sand hopper 10 is provided with aninternally threaded member 12 which is adapted to receive the upper endof threaded sleeve 13.

The lower end of the threaded sleeve 13 is connected to the upper end ofa valve housing 14 by suitable threads, as shown in FIG. 2. Projectingradially inwardly from the inner walls of the valve housing 14 areangularly spaced support members 16 which are adapted to support aball-like member 17. The lower end of the sleeve vupwardly in a mannerto be described hereinafter. erably, the ball-like member is formed of arubber-like Patented Mar. 30, 1955 material whereby the outer surfacethereof conforms to the surfaces of any sand particles which becomelodged between the ball-like member and the valve seat 18 while theball-like member is in sealing engagement with the valve seat.

The upper end of a downwardly extending conduit 19 is connected to thelower end of the valve housing 14 by a threaded joint 21. As shown inFIG. 1, the conduit 19 extends downwardly from the valve housing 14 asat 22 and terminates in an upwardly extending portion 23 which isconnected to a blow head 24 by a suitable threaded joint 26.

The blow head 24 is moved toward and away from a sand receiving member27 by suitable means, such as a cam member 28 which engages an annularrecess 29 provided in the blow head. Accordingly, upon rotation of thecam member 28, the blow head is moved toward or away from the sandreceiving member 27. That is, the cam member 2-8 moves the blow head 24into air-tight sealing relation with the sand receiving member 27 justprior to introduction of said therein. The sand receiving member 27 maybe in the form of a core or any other member which receives sand, suchas a sand-lined mold.

A lateral opening 31 is provided in the valve housing 14 slightly abovethe radially extending support members 16, as shown in FIG. 2, forreceiving a conduit 32 which is connected to an air supply conduit 33 bya solenoid actuated valve indicated generally at 34. The opening 31 isso positioned relative to the ball-like member 17 that upon introductionof compressed air into the valve housing 14, the ball-like member 17 isforced upwardly into sealing engagement with the valve seat 18. From theforegoing description, the operation of my improved apparatus forblowing sand into a sand receiving member will be readily understood. Atthe beginning of the cycle of operation, the entire apparatus from thesand hopper 11) to the discharge end of the blow head 24 is filled withsand. With the solenoid actuated valve 34 closed, the rubber ball-likemember 17 is supported on the radially extending members 16 whereby sandis free to flow by gravity around the ball-like member and between theradially extending members 16 into the conduit 19 whereby the conduit 19is automatically filled each time the solenoid actuated valve 34 isclosed.

To begin a cycle of operation, the cam member 28 is actuated by suitablemeans whereupon the blow head 24 is forced upwardly into sealingengagement with the bottom of the sand receiving member 27 to therebyform an air-tight seal. The solenoid actuated valve 34 is then openedwhereupon compressed air enters the valve hous ing 14 through theconduit 32. This results in a rapid pressure rise beneath the rubberball 17 which forces it upwardly into sealing engagement with the valveseat 18 whereby air cannot pass from the housing 14 into the hopper 10and sand cannot pass from the hopper 10 into the valve housing 14. Withthe ball 17 in sealing relation with the valve seat 18, the compressedair moves downwardly between the radially extending support members 16to thus force the column of sand through the conduit 19 to the sandreceiving member 27 to thus create a void area to the point V. Asuitable timer is associated with the apparatus whereby when the sandreceiving member 27 is filled with sand, the timer times out and thesolenoid actuated valve 34 is again closed. In view of the fact that thetimer mechanism forms no part of my invention and such apparatus is wellknown entering the sand receiving member.

in the art, not further detailed description thereof is deemednecessary.

Immediately upon movement of the solenoid actuated valve 34 to closedposition, there is a pressure drop within the housing 14 to atmosphericpressure whereby the blow head 24 may be retracted by actuating the cam28. Also, as the pressure within the valve housing 14 decreases toatmospheric pressure, the rubber ball-like member 17 returns to seatedposition on the radially extending support members 16, thus permittingthe sand to flow by gravity around the ball-like member 17 and betweenthe radially extending support members 16 into the conduit 19 whereuponthe void area is filled. The apparatus is then ready for another cycleof operation.

From the foregoing, it will be seen that I have devised an improvedapparatus for blowing sand into a sand receiving member. By transferringthe sand from a source of supply to the sand receiving member with aminimum of compressed air, the apparatus is not subjected to airblasting, thereby greatly increasing the life of the apparatus. Also, byforcing the column of sand in a positive manner through the conduit intothe sand receiving member, I provide a constant sand to air ratioFurthermore, by positively forcing the column of sand through theconduit to the sand receiving chamber there are no large expansionchambers.

While I have shown my invention in but one form, it will be obvious tothose skilled in the art that it is not so limited, but is susceptibleof various changes and modifications without departing from the spiritthereof, and I desire, therefore, that only such limitations shall beplaced thereupon as are specifically set forth in the appended claims.

What I claim is:

1. Apparatus for blowing sand into a sand receiving member comprising:

(a) a blow head adapted to communicate with the sand receiving memberand supply sand thereto,

(b) sand supply means,

(c) a conduit communicating at one end with said sand supply means andextending downwardly therefrom with the other end thereof extendingupwardly and communicating with said blow head in position to retain acolumn of sand in said other end and thereby prevent discharge of sandby gravity from said other end,

(d) air supply means communicating with said one end of said conduit,

(e) means to control the flow of air from said air supply means to saidconduit, and

(f) valve means operable in response to introduction of air into saidconduit to block the flow of sand from said sand supply means to saidconduit and to block the flow of air from said conduit to said sandsupply means to force sand through said blow head into said sandreceiving member and disposed to permit gravity flow of sand from saidsand supply means to said conduit in response to interruption of theflow of air from said air supply means to said conduit to fill saidconduit with sand.

2. Apparatus for blowing sand into a sand receiving member as defined inclaim 1 in which the valve means comprises:

(a) a valve housing communicating adjacent its upper end with said sandsupply means and communicating adjacent its lower end with said conduit,

(b) there being a lateral passageway through said housing intermediatesaid sand supply means and said conduit in communication with said airsupply means,

(0) inwardly extending support means within said housing,

(d) a ball-like member adapted to be supported by said support meanswithin said housing,

(e) said ball-like member and said support means being of a size topermit free flow of sand from said sand supply means to said conduitwhile the balllike member is supported by said support means, and

(f) a valve seat in said housing above said ball-like member disposed toreceive said ball-like member as it is forced upwardly in response tointroduction of air into said housing through said lateral passageway.

3. Apparatus for blowing sand into a sand receiving member as defined inclaim 2 in which the ball-like member is formed of a rubber-likematerial whereby the outer surface thereof conforms to the surfaces ofany sand particles between said ball-like member and said valve seatwhile the ball-like member is in sealing engagement with the valve seat.

4. Apparatus for blowing sand into a sand receiving member as defined inclaim 2 in which the inwardly extending support means is in the form ofradially extending members which are spaced angularly from each other topermit free flow of sand through said housing to said conduit while theball-like member is supported by said radially extending members.

5. Apparatus for blowing sand into a sand receiving member as defined inclaim 2 in which means is operatively connected to said blow head tomove said blow head into sealing engagement with the sand receivingmember prior to introduction of air into said housing.

References Cited by the Examiner UNITED STATES PATENTS 1,458,852 6/23Russell 222373 X 2,578,994 12/51 Dunaway 222-493 X 2,734,667 2/56Conklin 222-380 X 3,095,018 6/63 Moreland 222-373 X 3,102,666 9/63Fresnard 222373 3,104,782 9/63 Von Funk 222-373 X LOUIS J. DEMBO,Primary Examiner.

1. APPARATUS FOR BLOWING SAID INTO A SAND RECEIVING MEMBER COMPRISING:(A) A BLOW HEAD ADAPTED TO COMMUNICATE WITH THE SAND RECEIVING MEMBERAND SUPPLY SAID THERETO, (B) SAND SUPPLY MEANS, (C) A CONDUITCOMMUNICATING AT ONE END WITH SAID SAND SUPPLY MEANS AND EXTENDINGDOWNWARDLY THEREFROM WITH THE OTHER END THEREBY EXTENDING UPWARDLY ANDCOMMUNICATING WITH SAID BELOW HEAD IN POSITION TO RETAIN A COLUMN OFSAND IN SAID OTHER END AND THEREBY PREVENT DISCHARGE OF AND BY GRAVITYFROM SAID OTHER, END, (B) AIR SUPPLY MEANS COMMUNICATION WITH SAID ONEEND OF SAID CONDUIT, (E) MEANS TO CONTROL THE FLOW OF AIR FROM SAID AIRSUPPLY MEANS TO SAID CONDUIT, AND (F) VALVE MEANS OPERABLE IN RESPONSETO INTRODUCTION OF AIR INTO SAID CONDUIT TO BLOCK THE FLOW OF SAND FROMSAID SAND SUPPLY MEANS TO SAID CONDUIT AND TO BLOCK THE FLOW OF AIR FROMSAID CONDUIT TO SAID SAND SUPPLY MEANS TO FORCE SAND THROUGH SAID BLOWHEAD INTO SAID SAND RECEIVING MEMBER AND DISPOSED TO PERMIT GRAVITY FLOWOF SAND FROM SAID SAND SUPPLY MEANS TO SAID CONDUIT IN RESPONSE TOINTERRUPTION OF THE FLOW OF AIR FROM SAID AIR SUPPLY MEANS TO SANDCONDUIT TO FILL SAID CONDUIT WITH SAND.